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| author | H.J. Lu <hjl.tools@gmail.com> | 2024-03-15 07:04:33 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2024-03-22 10:17:11 +0100 |
| commit | 2883f01ec37dd8668e7222dfdb5980c86fdfe277 (patch) | |
| tree | 79901073cd1ccb6d373dfc910aa5d6258bedba74 | |
| parent | 4ae3dc83b047d51485cce1a72be277a110d77c91 (diff) | |
| download | linux-stable-2883f01ec37dd8668e7222dfdb5980c86fdfe277.tar.gz linux-stable-2883f01ec37dd8668e7222dfdb5980c86fdfe277.tar.bz2 linux-stable-2883f01ec37dd8668e7222dfdb5980c86fdfe277.zip | |
x86/shstk: Enable shadow stacks for x32
1. Add shadow stack support to x32 signal.
2. Use the 64-bit map_shadow_stack syscall for x32.
3. Set up shadow stack for x32.
Tested with shadow stack enabled x32 glibc on Intel Tiger Lake:
I configured x32 glibc with --enable-cet, build glibc and
run all glibc tests with shadow stack enabled. There are
no regressions. I verified that shadow stack is enabled
via /proc/pid/status.
Signed-off-by: H.J. Lu <hjl.tools@gmail.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: H.J. Lu <hjl.tools@gmail.com>
Cc: "Edgecombe, Rick P" <rick.p.edgecombe@intel.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Link: https://lore.kernel.org/r/20240315140433.1966543-1-hjl.tools@gmail.com
| -rw-r--r-- | arch/x86/entry/syscalls/syscall_64.tbl | 2 | ||||
| -rw-r--r-- | arch/x86/kernel/shstk.c | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/signal_64.c | 6 |
3 files changed, 9 insertions, 3 deletions
diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 7e8d46f4147f..cc78226ffc35 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -374,7 +374,7 @@ 450 common set_mempolicy_home_node sys_set_mempolicy_home_node 451 common cachestat sys_cachestat 452 common fchmodat2 sys_fchmodat2 -453 64 map_shadow_stack sys_map_shadow_stack +453 common map_shadow_stack sys_map_shadow_stack 454 common futex_wake sys_futex_wake 455 common futex_wait sys_futex_wait 456 common futex_requeue sys_futex_requeue diff --git a/arch/x86/kernel/shstk.c b/arch/x86/kernel/shstk.c index 59e15dd8d0f8..6f1e9883f074 100644 --- a/arch/x86/kernel/shstk.c +++ b/arch/x86/kernel/shstk.c @@ -163,8 +163,8 @@ static int shstk_setup(void) if (features_enabled(ARCH_SHSTK_SHSTK)) return 0; - /* Also not supported for 32 bit and x32 */ - if (!cpu_feature_enabled(X86_FEATURE_USER_SHSTK) || in_32bit_syscall()) + /* Also not supported for 32 bit */ + if (!cpu_feature_enabled(X86_FEATURE_USER_SHSTK) || in_ia32_syscall()) return -EOPNOTSUPP; size = adjust_shstk_size(0); diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c index 23d8aaf8d9fd..8a94053c5444 100644 --- a/arch/x86/kernel/signal_64.c +++ b/arch/x86/kernel/signal_64.c @@ -315,6 +315,9 @@ int x32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) uc_flags = frame_uc_flags(regs); + if (setup_signal_shadow_stack(ksig)) + return -EFAULT; + if (!user_access_begin(frame, sizeof(*frame))) return -EFAULT; @@ -377,6 +380,9 @@ COMPAT_SYSCALL_DEFINE0(x32_rt_sigreturn) if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags)) goto badframe; + if (restore_signal_shadow_stack()) + goto badframe; + if (compat_restore_altstack(&frame->uc.uc_stack)) goto badframe; |